JP4480264B2 - Insertion light source - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an insertion light source capable of generating circularly or elliptically polarized radiation.
[0002]
[Prior art]
When an electron beam accelerated to near the speed of light in a vacuum is bent in a magnetic field, emitted light is emitted in the tangential direction of the movement trajectory of the electron beam, and this is called synchrotron radiation. A light source that generates synchrotron radiation is installed in the straight section of an electron storage ring (electron beam storage ring), and various technologies that utilize characteristics such as high directivity, high intensity, and high polarization are utilized. Research is underway to make it easier. Today's electron storage rings are provided with a plurality of insertion light sources (undulators) which are high-intensity light sources with higher beam current and smaller beam cross-sectional area.
[0003]
Here, when a relativistic electron beam is passed through a magnetic circuit in which the horizontal and vertical magnetic fields change spirally, the electrons move along a spiral trajectory, and high-intensity quasi-monochromatic circularly polarized radiation is emitted. Is known to be obtained. As a method for producing a magnetic circuit for generating such circularly polarized radiation, there is a method using an electromagnet using a bifilar coil, but a method using a permanent magnet is more general, and a typical example is shown in FIG. As shown in FIG.
[0004]
In FIG. 14, a first magnetic circuit device J1 located on the lower side and a second magnetic circuit device J2 located on the upper side are provided so as to sandwich a gap space δ through which an electron beam passes. The first magnetic circuit device J1 includes a first magnet row m1 located in the center row thereof, and a third magnet row m3 and a fourth magnet row m4 arranged on both sides in the width direction of the first magnet row m1. . The second magnetic circuit device J2 includes a second magnet row m2 located in the center row thereof, and a fifth magnet row m5 and a sixth magnet row m6 disposed on both sides in the width direction of the second magnet row m2. .
[0005]
The first magnet array m1 and the second magnet array m2 are in a positional relationship facing each other across the gap space δ, and are provided to generate a vertical magnetic field.
The third magnet row m3 and the fifth magnet row m5 are in a positional relationship facing each other across the gap space δ, and are provided to generate a horizontal magnetic field.
The fourth magnet row m4 and the sixth magnet row m6 are in a positional relationship facing each other across the gap space δ, and are provided to generate a horizontal magnetic field.
[0006]
Each of the magnet arrays m1 to m6 has the same period length L, and a large number of magnets are regularly arranged along the array direction (direction in which the electron beam travels). Moreover, what is indicated by an arrow in each magnet indicates the magnetized direction.
[0007]
Here, the positions of the center first magnet array m1 and the second magnet array m2 are fixed, and the third magnet array m3 and the fourth magnet array m4 on both sides of the first magnet array m1 Are driven in the row direction (direction in which the electron beam travels) in opposite directions, and in conjunction with this, the fifth magnet row m5 and the sixth magnet on both sides of the second magnet row m2 are interlocked with this. The column m6 is driven in the column direction in the opposite direction to each other, thereby forming a helical magnetic field and generating circularly polarized (or elliptically polarized) radiation. Explaining in the figure, the magnet array is driven so that the states of FIGS. 14A and 14B are alternately repeated periodically. Various physical properties studies such as magnetic studies of materials have been conducted using circularly polarized light as described above.
[0008]
In the configuration of FIG. 14, the first and second magnetic circuit devices J1 and J2 are each composed of three rows of magnets, but as shown in FIG. 15, the first and second magnetic circuit devices J1 and J2 are Some are composed of two rows of magnets.
In FIG. 15, a first magnetic circuit device J1 located on the lower side and a second magnetic circuit device J2 located on the upper side are provided so as to sandwich a gap space δ through which an electron beam passes. The first magnetic circuit device J1 includes a first magnet row m11 located on the left side in the drawing and a third magnet row m13 disposed on one side in the width direction of the first magnet row m11. The second magnetic circuit device J2 includes a second magnet row m12 located on the left side in the drawing and a fourth magnet row m14 arranged on one side in the width direction of the second magnet row m12.
[0009]
The 1st magnet row | line | column m11 and the 2nd magnet row | line | column m12 are in the positional relationship which opposes on both sides of the gap space (delta).
The third magnet row m13 and the fourth magnet row m14 are in a positional relationship facing each other across the gap space δ.
These four rows of magnets provide a vertical magnetic field and a horizontal magnetic field that is arranged with a ¼ period deviation from the vertical magnetic field. A helical magnetic field is obtained as a combination of these vertical and horizontal magnetic fields.
[0010]
Each of the magnet arrays m11 to m14 has the same period length L, and a large number of magnets are regularly arranged along the array direction (direction in which the electron beam travels). Moreover, what is indicated by an arrow in each magnet indicates the magnetized direction.
[0011]
Here, the positions of the first magnet row m11 and the fourth magnet row m14 that are diagonally arranged are fixed, and the second magnet row m12 and the third magnet row m13 are synchronized in the same direction. By being driven in the direction in which the electron beam travels, a helical magnetic field is formed, and circularly polarized (or elliptically polarized) radiation is created. Explaining in the figure, the magnet array is driven so that the states of FIGS. 15A, 15B, and 15C are alternately and periodically repeated.
[0012]
[Problems to be solved by the invention]
However, in the prior art of FIG. 14, when a pair of magnet rows on both sides of the center magnet row are driven relative to each other, an attractive repulsive force is generated by the center magnet row. It cannot be driven at high speed. In particular, in order to study physical properties with circularly polarized radiation with higher accuracy, it is necessary to switch between left and right circularly polarized light at high speed, and for this purpose, a pair of magnet arrays on both sides must be driven at high speed. . Further, with respect to the prior art of FIG. 15 as well, if the magnet rows are driven relative to each other, the attraction and repulsive force is similarly generated, so that high speed driving cannot be performed.
[0013]
Theoretically, it seems that high-speed driving can be realized by increasing the power of the motor for driving the magnet array, but the attraction repulsive force described above is very large, and high-speed driving is possible by powering up the motor. Is virtually impossible to achieve.
[0014]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an insertion light source capable of switching between left and right circularly polarized light and the like at high speed without increasing the power of a drive motor so much. .
[0015]
[Means for Solving the Problems]
To achieve the above object, the insertion light source according to the present invention will be described with reference to FIG.
A first magnetic circuit device (J1) and a second magnetic circuit device (J2) disposed so as to sandwich a gap space through which an electron beam passes;
A first magnet array (m1) for generating a vertical magnetic field provided in the first magnetic circuit device (J1);
The second magnet array (m2) for generating the vertical magnetic field provided in the second magnetic circuit device (J2) and disposed opposite to the first magnet array (m1) across the gap space;
A third magnet array (m3) for generating a horizontal magnetic field and a fourth magnet array (m4) provided on the first magnetic circuit device (J1) and disposed on both sides in the width direction of the first magnet array (m1). )When,
Provided in the second magnetic circuit device (J2), on both sides in the width direction of the second magnet row (m2) across the gap space, the third magnet row (m3) and the fourth magnet across the gap space. A fifth magnet row (m5) for generating the horizontal magnetic field and a sixth magnet row (m6) disposed opposite to the magnet row (m4);
A first drive mechanism that relatively drives the third magnet row (m3) and the fourth magnet row (m4) along the row direction with respect to the first magnet row (m1);
A second drive mechanism that relatively drives the fifth magnet row (m5) and the sixth magnet row (m6) along the row direction with respect to the second magnet row (m2);
During the relative driving of each magnet row by the first drive mechanism and the second drive mechanism, between the first magnet row (m1) and the third magnet row (m3) and the fourth magnet row (m4), And a magnetic circuit device for cancellation (m7, 8, 9, 10) that reduces or cancels the attractive repulsive force generated between the second magnet array (m2) and the fifth magnet array (m5) and the sixth magnet array (m6). ).
[0016]
For reference, figure numbers are attached with parentheses.
According to this configuration, a canceling magnetic circuit device is provided in addition to the configuration of the prior art shown in FIG. Thereby, when driving each magnet row | line, the attractive repulsion force by a 1st, 2nd magnet row | line | column can be reduced or canceled. Therefore, each magnet array can be driven at high speed without using a motor with such a large power as a drive source. As a result, it was possible to provide an insertion light source capable of switching left and right circularly polarized light at high speed without increasing the power of the drive motor so much.
[0017]
As for the first drive mechanism and the second drive mechanism, a drive source may be provided separately, or a common drive source may be used for the first drive mechanism and the second drive mechanism. It falls within the framework of the present invention.
[0018]
The present inventionPertaining toThe canceling magnetic circuit device includes a canceling seventh magnet array (m7) and an eighth magnet array (m7) and an eighth magnet array (m7) and an eighth magnet array ( m8), and a ninth magnet row (m9) and a tenth magnet row (m10) for cancellation arranged further outside in the width direction of the fifth magnet row (m5) and the sixth magnet row (m6). HaveThe
[0019]
According to this configuration, the seventh magnet row is arranged outside the third magnet row, the eighth magnet row is arranged outside the fourth magnet row, the ninth magnet row is arranged outside the fifth magnet row, and the sixth magnet is arranged. Tenth magnet rows are respectively arranged outside the rows. Therefore, since it is not necessary to increase the size of the configuration of the magnetic circuit, the insertion light source itself can be prevented from increasing in size.
[0020]
The present inventionFurthermore,The arrangement cycle of the magnets constituting the seventh magnet row and the eighth magnet row for cancellation and the arrangement cycle of the magnets constituting the first magnet row are the same,And, the magnets constituting the seventh magnet row and the eighth magnet row corresponding in the width direction and the magnetizing directions of the magnets constituting the first magnet row are all reversed or all the same.
The arrangement cycle of the magnets constituting the ninth magnet row and the tenth magnet row for cancellation and the arrangement cycle of the magnets constituting the second magnet row are made the same.In addition, the magnetizing directions of the magnets constituting the ninth magnet row and the tenth magnet row corresponding to the width direction and the magnets constituting the second magnet row are all reversed or the same. Yes.
[0021]
According to this configuration, since the arrangement period (period length) of the magnets is the same, the attractive repulsive force can be effectively reduced or canceled.
[0022]
As still another preferred embodiment of the present invention, the first drive mechanism includes a pair of crank mechanisms having a common crankshaft, whereby the third magnet row, the fourth magnet row, Can be reciprocally driven in opposite directions.
[0023]
According to this configuration, the third and fourth magnet arrays can be driven in conjunction with the common crankshaft via the pair of crank mechanisms. When the third magnet row and the fourth magnet row are driven by separate and independent mechanisms, a so-called synchronization shift occurs, but according to the above configuration, the third and fourth magnet rows are driven with high accuracy. be able to.
[0024]
As another preferred embodiment of the present invention, a crankshaft provided with a weight part having a flywheel effect can be mentioned.
According to this configuration, the third and fourth magnet rows can be smoothly moved by the flywheel effect.
[0025]
As still another preferred embodiment of the present invention, a base member that supports the third magnet row and a base member that supports the fourth magnet row are separately provided, and a horizontal plane and a vertical surface of each base member are provided. The thing provided with the linear guide mechanism to guide is mention | raise | lifted.
[0026]
Between the magnet rows facing each other across the gap space, there is a possibility that the bending deformation of the holding member holding each magnet row may occur due to the acting repulsive force. By providing a linear guide mechanism for guiding, the bending deformation can be eliminated.
[0027]
As still another preferred embodiment of the present invention, the second drive mechanism includes a pair of crank mechanisms having a common crankshaft, whereby the fifth magnet row, the sixth magnet row, and the like. Are configured to be reciprocally driven in opposite directions,
Examples include a synchronization mechanism that synchronously drives the first drive mechanism and the second drive mechanism.
[0028]
In order to generate desired circularly polarized (or elliptically polarized) radiation, it is necessary to drive the movement of the magnet array in the first magnetic circuit device and the movement of the magnet array in the second magnetic circuit device in synchronization with each other. is there. Thus, as described above, desired circularly polarized radiation can be obtained by synchronously driving the first drive mechanism and the second drive mechanism.
[0029]
To achieve the object of the present invention, another insertion light source according to the present invention will be described with reference to FIG. 10. A first magnetic circuit device (J1) arranged so as to sandwich a gap space through which an electron beam passes, and , A second magnetic circuit device (J2), a first magnet array (m21) for magnetic field generation provided in the first magnetic circuit device (J1), and a second magnetic circuit device (J2). The first magnet array is provided in the second magnet array (m22) for generating a magnetic field disposed opposite to the first magnet array (m21) across the gap space, and the first magnetic circuit device (J1). A third magnet array (m23) for generating a magnetic field arranged on one side in the width direction of (m21) and one in the width direction of the second magnet array (m22) provided in the second magnetic circuit device (J2). The third magnet row (with the gap space in between) The third magnet row (m23) is driven in the row direction relative to the fourth magnet row (m24) for generating a magnetic field and opposite to the first magnet row (m21). A first drive mechanism, a second drive mechanism that relatively drives the second magnet row (m22) in the row direction with respect to the fourth magnet row (m24), the first drive mechanism, and the second drive. A canceling magnetic circuit device that reduces or cancels the attractive repulsion force that occurs during the relative driving of each magnet row by the mechanism, and the canceling magnetic circuit device includes the third magnet row (m23). A fifth magnet row for cancellation (m25) disposed on the outer side in the width direction opposite to the side on which one magnet row (m21) is disposed, and the fourth magnet row of the second magnet row (m22). (M24) on the side opposite to the side where Sixth Bei a magnet row (m26) for canceling disposed outwardlye,
The arrangement cycle of the magnets constituting the fifth magnet row (m25) and the arrangement cycle of the magnets constituting the first magnet row (m21) are the same and correspond to each other in the width direction. Magnets constituting the magnet array (m25) and magnets constituting the first magnet array (m21) are all reversed or all the same.
The sixth magnet, wherein the arrangement period of the magnets constituting the six-magnet array (m26) and the arrangement period of the magnets constituting the second magnet array (m22) are the same and correspond in the width direction Magnets constituting the row (m26) and magnets constituting the second magnet row (m22) are all reversed or all the same.It is characterized by this. For reference, figure numbers are attached with parentheses.
[0030]
According to this configuration, a canceling magnetic circuit device is provided in addition to the configuration of the prior art shown in FIG. Thereby, when driving the second and third magnet rows, the attractive repulsive force generated between the first and fourth magnet rows can be reduced or canceled. Therefore, each magnet array can be driven at high speed without using a motor with such a large power as a drive source. As a result, it was possible to provide an insertion light source capable of switching polarization at high speed without increasing the power of the drive motor so much.As for the first drive mechanism and the second drive mechanism, a drive source may be provided separately, or a common drive source may be used for the first drive mechanism and the second drive mechanism. It falls within the framework of the present invention.
[0031]
DETAILED DESCRIPTION OF THE INVENTION
A preferred first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram of a magnetic circuit constituting an insertion light source according to the present invention. For convenience of explanation, XYZ coordinate axes are shown.
[0032]
<Configuration of Magnetic Circuit of First Embodiment>
In FIG. 1, a first magnetic circuit device J1 located on the lower side and a second magnetic circuit device J2 located on the upper side are provided so as to sandwich a gap space δ through which an electron beam passes. The first magnetic circuit device J1 includes a first magnet row m1 located in the center row thereof, a third magnet row m3 and a fourth magnet row m4 disposed on both sides in the width direction of the first magnet row m1, and a third magnet. A seventh magnet row m7 located further outside the row m3 and an eighth magnet row m8 located further outside the fourth magnet row m4 are provided.
[0033]
The second magnetic circuit device J2 includes a second magnet row m2 located in the center row, fifth and sixth magnet rows m5 and m6 disposed on both sides in the width direction of the second magnet row m2, and a fifth magnet. A ninth magnet row m9 located further outside the row m5 and a tenth magnet row m10 located further outside the sixth magnet row m6 are provided.
[0034]
The first magnet array m1 and the second magnet array m2 are in a positional relationship facing each other across the gap space δ, and are provided to generate a vertical magnetic field.
The third magnet row m3 and the fifth magnet row m5 are in a positional relationship facing each other across the gap space δ, and are provided to generate a horizontal magnetic field.
The fourth magnet row m4 and the sixth magnet row m6 are in a positional relationship facing each other across the gap space δ, and are provided to generate a horizontal magnetic field.
[0035]
The seventh magnet row m7 and the ninth magnet row m9 are in a positional relationship facing each other across the gap space δ, and function as a canceling magnet row that will be described later.
The eighth magnet array m8 and the tenth magnet array m10 are in a positional relationship facing each other across the gap space δ, and these also function as a canceling magnet array.
[0036]
Each of the magnet arrays m1 to m10 has the same magnet array pitch and the same periodic length L, and a large number of magnets are regularly arrayed along the array direction (direction in which the electron beam travels: Z-axis direction). . Moreover, what is indicated by an arrow in each magnet indicates the magnetized direction.
[0037]
The first and second magnet arrays m1 and m2 located in the center of the magnetic circuit devices J1 and J2 are fixed and held. Further, the seventh to tenth magnet rows m7 to 10 which are canceling magnet rows are also fixed and held.
[0038]
The third magnet row m3 and the fourth magnet row m4 are interlocked in directions opposite to each other with respect to the central first magnet row m1 (indicated by arrows A (Z direction) and B (−Z direction) in FIG. 1). And can be reciprocated. By reciprocating, it is driven to periodically switch between the state shown in FIG. 1 and the state shown in FIG.
[0039]
The fifth magnet row m5 and the sixth magnet row m6 are interlocked with each other in the opposite directions (indicated by arrows C (−Z direction) and D (Z direction) in FIG. 1) with respect to the central second magnet row m2. And can be reciprocated. By reciprocating, similarly, it is driven to periodically switch between the state shown in FIG. 1 and the state shown in FIG.
[0040]
As can be seen from FIGS. 1 and 2, the upper and lower magnet rows are driven in conjunction with each other so that the third magnet row m3 and the sixth magnet row m6 are driven in the same direction. The fourth magnet row m4 and the fifth magnet row m5 are configured in the same direction, and are driven in the opposite direction to the third and sixth magnet rows m3 and m6.
By driving as described above, desired circularly polarized (elliptically polarized) radiation can be obtained.
[0041]
<Cancel magnet row>
By the way, when the third and fourth magnet rows m3 and m4 are driven in the row direction relative to the fixed first magnet row m1, the third repulsive force received from the first magnet row m1 causes the third. When the fourth magnet arrays m3 and m4 are driven, they become a load and cannot be driven at high speed. This is the same when the fifth and sixth magnet rows m5 and m6 are driven in the row direction with respect to the second magnet row m2.
[0042]
Therefore, in order to reduce or cancel the load due to the attractive repulsive force, a canceling magnet array m7 to m10 is provided. The canceling magnet rows m7 to m10 are the magnet rows m7, m8, m9, and m10 arranged on the outer side of the driven magnet rows m3 to m6, as described above. That is, as the magnet row, the first and second magnetic circuit devices have five rows. The canceling magnet rows m7 to 10 are fixed and do not move.
[0043]
Here, the periodic length L of each of the magnet arrays m1 to 10 is the same, and four magnets are configured as one unit.
The first magnet array m1 is from the top of FIG.
Magnets are periodically arranged in the order of (Y) → (−Z) → (−Y) → (Z). Here, (Y) is a symbol that means a magnet magnetized in the Y direction, and the same applies to other cases.
[0044]
The second magnet array m2 is from the top of FIG.
Magnets are periodically arranged in the order of (Y) → (Z) → (−Y) → (−Z). This creates a vertical magnetic field.
[0045]
The third and fourth magnet rows m3 and m4 are from the top of FIG.
Magnets are periodically arranged in the order of (Y) → (−Z) → (−Y) → (Z). That is, it is the same as the first magnet array m1.
[0046]
The fifth and sixth magnet rows m5 and m6 have the same magnet arrangement as the second magnet row m2.
[0047]
That is, when these third to sixth magnet arrays m3 to m6 are not driven (in this case, the head positions of the magnet arrays m1 to m10 are aligned), linearly polarized radiation can be generated. It can create a magnetic field that fluctuates in a spiral when driven.
[0048]
Next, the seventh and eighth magnet arrays m7 and m8 for cancellation in the first magnetic circuit device J1 are as shown in FIG.
Magnets are periodically arranged in the order of (−Y) → (Z) → (Y) → (−Z). In other words, the magnetization direction of the corresponding magnet in the X direction is opposite to that of the magnet constituting the first magnet row m1. Therefore, it is possible to reduce or cancel the attractive repulsion force in the column direction (z direction) by the first magnet row m1 when driving the third and fourth magnet rows m3 and m4. Moreover, it can cancel effectively by making the periodic length L of the magnet arrangement | sequence of the 1st magnet row | line | column m1 and the 7th, 8th magnet row | line | column m7, m8 the same.
[0049]
The ninth and tenth magnet rows m9 and m10 for cancellation in the second magnetic circuit device J2 are also in the opposite magnetization direction to the magnets constituting the second magnet row m2, thereby the fifth and sixth magnet rows. It is possible to reduce or cancel the attractive repulsion force in the row direction (z direction) by the second magnet row m2 when driving m5 and m6.
[0050]
<Configuration of drive device>
Next, the configuration of the insertion light source including the drive mechanism for driving the first and second magnetic circuit devices J1 and J2 shown in FIGS. 1 and 2 is shown in FIGS. 3 is a plan view, FIG. 4 is a view in the direction of arrow P (front view) in FIG. 5, and FIG. 5 is a side view. Since the first drive mechanism of the first magnetic circuit device J1 and the second drive mechanism of the second magnetic circuit device J2 have the same configuration, only the drive mechanism of the first magnetic circuit device J1 will be described here. The description regarding the second magnetic circuit device J2 is omitted.
[0051]
First, the holding mechanism will be described. A large lower base 1 is disposed at the center, and a first intermediate base 2 and a second intermediate base 3 are coupled to each other by bolts. Each magnet constituting the central first magnet row m1 is fixed to the second intermediate base 3 by a coupling shaft member 4. The left side base 5 and the right side base 6 are respectively coupled to the left and right sides of the lower base 1 by bolts or the like.
[0052]
An intermediate support member 7 is fixed to the upper portion of the left side base 5 with a bolt, and a cancel magnet support member 8 is fixed to the intermediate support member 7 with a bolt. The magnets constituting the canceling eighth magnet row m8 are fixed to the canceling magnet support member 8 by the first pressing member 9 and the second pressing member 10. Further, an intermediate support member 7, a cancel magnet support member 8, and first and second presser members 9 and 10 are also provided on the right side base 6 side symmetrically in FIG. Each magnet constituting the magnet array m7 is fixed.
[0053]
Next, a holding mechanism for the moving fourth magnet row m4 will be described. A first support member 12 and a second support member 13 are sequentially fixed with bolts or the like on a moving base 11 (corresponding to a base member), and a magnet support member 14 with respect to the second support member 13. Is fixed with bolts. Each magnet constituting the moving fourth magnet row m4 is fixed by a third pressing member 15 and a fourth pressing member 16. Further, the moving third magnet row m3 is also held by the same method. The moving base 11 includes a linear guide mechanism 17 on a lower horizontal plane, and linear guide mechanisms 18 and 19 on left and right vertical surfaces. Thereby, the bending deformation of the up-down and left-right directions by the attractive repulsive force which the 3rd, 4th magnet row | line m3, m4 to drive receives from another magnet row | line can be eliminated. As the linear guide mechanism, a configuration using a known circulating ball mechanism (for example, trade name LM guide) can be employed.
[0054]
As can be seen from the plan view of FIG. 3, the width dimension of the magnets at both ends of each of the magnet arrays m1, m3, m4, m7, m8 is half that of the other magnets.
[0055]
In order to drive the third and fourth magnet arrays m3 and m4, the third and fourth magnet arrays m3 and m4 are driven via a crankshaft 20 connected to a pulse motor (not shown) and a crank mechanism K. Both ends of the crankshaft 20 are supported by bearings 21 and 22, and a first crank member 23 and a second crank member 24 constituting the crank mechanism K are integrally formed. The first and second crank members 23 and 24 have the same shape, but are connected to the crankshaft 20 in an eccentric state by the amount of eccentricity e from the center of the crankshaft 20, and the first crank. The eccentric directions of the member 23 and the second crank member 24 are opposite to each other by 180 degrees. The first and second crank members 23 and 24 are connected to a connecting portion 12 a formed on the first support member 12 by a connecting shaft 26. In addition, a weight portion 25 having a flywheel effect is provided in the central portion of the crankshaft 20 in the axial direction. As a result, stable driving of the third and fourth magnet arrays m3 and m4 is realized. The crank mechanism K and the like described above are assembled on the support base 27.
[0056]
By rotating the crankshaft 20 with a pulse motor (not shown) as a motor (not shown), the third and fourth magnet arrays m3 and m4 can be reciprocated at a predetermined cycle. it can. Since the eccentric directions of the first and second crank members 23 and 24 are opposite directions, the third magnet row m3 and the fourth magnet row m4 are driven in opposite directions. In the present embodiment, the amount of eccentricity e is the width of one magnet, but is not particularly limited thereto. By providing the canceling magnet rows m7 and m8, high-speed driving of 2 Hz or more (preferably 3 to 10 Hz) can be realized.
[0057]
The first magnet array m1 in the center of the magnet array is for generating a vertical magnetic field, and the horizontal magnetic field is generated by driving the third and fourth magnet arrays m3 and m4 on the left and right sides in opposite directions. In addition, the direction of the magnetic field is changed by reciprocating driving, and the spiral trajectory of the electron beam passing through the gap space is changed from right-handed to left-handed. It can be changed with polarized light.
[0058]
<Drive block diagram>
FIG. 6 is a block diagram of the drive mechanism. The third and fourth magnet rows m3 and m4 of the first magnetic circuit device J1 and the fifth and sixth magnet rows m5 and m6 of the second magnetic circuit device J2 need to be driven in synchronization. Therefore, a synchronization mechanism D1 for synchronizing and driving the pulse motor of the first drive mechanism and the pulse motor of the second drive mechanism is provided and is controlled by the control device CO. Instead of the electrical synchronization mechanism D1, a synchronization mechanism D2 in which the crank mechanisms K of the first and second drive mechanisms are mechanically connected in synchronization may be employed. Note that the first and second drive mechanisms may be driven by one pulse motor.
[0059]
<Effect of canceling magnet array>
Next, the effect of the canceling magnetic circuit device using the canceling magnet array will be described using graphs.
FIG. 7 is a graph showing the effect (theoretical calculation value) when the canceling magnetic circuit device is used. As a condition, the periodic length is 60 mm, and the gap interval through which the electron beam passes is 20 mm. Δ on the horizontal axis is the amount of movement (mm) in the column direction. The vertical axis represents the attractive repulsion force Fz (N / m) per 1 m of moving magnet array in the z-axis (see FIG. 1) direction. In the graph, black ◇ indicates a case where no canceling magnetic circuit device is provided, and ○ indicates a case where a canceling magnetic circuit device is provided, and the effect is apparent from the graph.
[0060]
<Configuration of Magnetic Circuit of Second Embodiment>
Next, the configuration of the magnetic circuit of the second embodiment is shown in FIG. The difference from the first embodiment of FIG. 1 is the magnetization directions of the canceling magnet arrays m7, m8, m9, m10, and the other configurations are the same. As shown in FIG. 9, it can be understood that the suction repulsion force in the x-axis direction is reduced as a result of this configuration.
[0061]
<Third Embodiment>
Next, the configuration of the magnetic circuit of the third embodiment will be described.
[0062]
In FIG. 10, the first magnetic circuit device J1 includes a first magnet row m21, a third magnet row m23 arranged adjacent to one side (right side in the drawing) of the first magnet row m21, and a third magnet row m23. And a fifth magnet row m25 adjacent to the outside in the width direction.
[0063]
The second magnetic circuit device J2 includes a second magnet row m22, a fourth magnet row m24 arranged adjacent to one side (right side in the drawing) of the second magnet row m22, and the outer side in the width direction of the second magnet row m12. And a sixth magnet row m26 adjacent to the first magnet row m26.
[0064]
Each of the magnet arrays m21 to m24 is provided to generate a magnetic field that spirally changes in the z direction as a combination of the vertical and horizontal magnetic fields, like the magnet arrays m11 to m14 of FIG.
The fifth magnet row m25 and the sixth magnet row m26 function as canceling magnet rows. It is characterized in that the canceling magnet array is arranged only on one side (disposed diagonally).
The magnetizing directions and arrangement periods of the magnets constituting each magnet array m21 to m26 are as shown in FIG.
The first and fourth magnet rows m21 and m24 and the fifth and sixth magnet rows m25 and m26 which are canceling magnet rows are fixed and held.
[0065]
The second magnet array m22 and the third magnet array m23 that are arranged diagonally to each other are configured to reciprocate in conjunction with the fixed magnet arrays m21, m24, m25, and m26. By reciprocating, it is driven so as to periodically switch to the states of (a), (b) and (c) of FIG.
[0066]
By driving as described above, a desired spiral magnetic field can be formed, and circularly polarized (or elliptically polarized) radiation can be obtained.
According to the configuration of the third embodiment, the number of canceling magnet rows may be two, and the number of driving magnet rows may be two. Therefore, the configuration of the entire insertion light source can be reduced, and the drive mechanism The configuration can also be simplified.
[0067]
The effect of using the canceling magnetic circuit device shown in FIG. 10 is shown in FIG. In the graph, black ◇ indicates a case where no canceling magnetic circuit device is provided, and ○ indicates a case where a canceling magnetic circuit device is provided. The effect is clear from the graph, and the suction repulsive force in the z-axis direction can be reduced.
[0068]
<Configuration of Magnetic Circuit of Fourth Embodiment>
Next, the configuration of the magnetic circuit of the fourth embodiment is shown in FIG. The difference from the third embodiment in FIG. 10 is the magnetization direction of the canceling magnet arrays m25 and m26, and the other configurations are the same. As shown in FIG. 13, it can be seen that the suction repulsion force in the x-axis direction is reduced as a result of this configuration.
[0069]
In the third and fourth embodiments, the canceling magnet rows are arranged only on one side of the two magnet rows, but a configuration arranged on both sides of the two rows of magnet rows may be adopted. .
[0070]
【The invention's effect】
As described above, according to the configuration of the present invention, a canceling magnetic circuit device is provided in addition to the configuration of the prior art shown in FIGS. Thereby, the attractive repulsive force generated when each magnet row is driven can be reduced or canceled. Therefore, it is possible to drive each magnet array at high speed without using a motor with a large power as a driving source. As a result, it was possible to provide an insertion light source capable of switching between left and right circularly polarized light at high speed without increasing the power of the drive motor so much.
[Brief description of the drawings]
FIG. 1 is a schematic diagram (1) of a magnetic circuit constituting an insertion light source according to a first embodiment.
FIG. 2 is a schematic diagram (2) of a magnetic circuit constituting the insertion light source according to the first embodiment.
FIG. 3 is a plan view showing a configuration of an insertion light source including a driving mechanism.
FIG. 4 is a front view showing the configuration of an insertion light source including a drive mechanism (as viewed from arrow P in FIG. 5).
FIG. 5 is a side view showing the configuration of an insertion light source including a drive mechanism.
FIG. 6 is a drive block diagram.
FIG. 7 is a graph showing the effect when a canceling magnetic circuit device is used.
FIG. 8 is a schematic diagram of a magnetic circuit constituting the insertion light source according to the second embodiment.
FIG. 9 is a graph showing the effect of the second embodiment.
FIG. 10 is a schematic diagram of a magnetic circuit constituting the insertion light source according to the third embodiment.
FIG. 11 is a graph showing the effect of the third embodiment.
FIG. 12 is a schematic diagram of a magnetic circuit constituting the insertion light source according to the fourth embodiment.
FIG. 13 is a graph showing the effect of the fourth embodiment.
FIG. 14 is a schematic diagram of a magnetic circuit according to the prior art (1).
FIG. 15 is a schematic diagram of a magnetic circuit according to the prior art (2).
[Explanation of symbols]
11 Moving base
17, 18, 19 Linear guide mechanism
20 Crankshaft
25 parts by weight
K crank mechanism
J1 First magnetic circuit device
J2 Second magnetic circuit device
m1, m2 1st magnet row, 2nd magnet row
m3, m4 3rd magnet row, 4th magnet row
m5, m6 5th magnet row, 6th magnet row
m7, m8 7th magnet row, 8th magnet row
m9, m10 9th magnet row, 10th magnet row
m11, m12 1st magnet row, 2nd magnet row
m13, m14 3rd magnet row, 4th magnet row
m15, m16 5th magnet row, 6th magnet row
m17, m18 7th magnet row, 8th magnet row
m21, m22 1st magnet row, 2nd magnet row
m23, m24 3rd magnet row, 4th magnet row
m25, m26 5th magnet row, 6th magnet row
L Period length
δ Gap space

Claims (6)

A first magnetic circuit device and a second magnetic circuit device arranged so as to sandwich a gap space through which an electron beam passes;
A first magnet array for generating a vertical magnetic field provided in the first magnetic circuit device;
The second magnetic circuit for generating a vertical magnetic field, which is provided in the second magnetic circuit device and is arranged to face the first magnet array with the gap space in between;
A third magnet row for generating a horizontal magnetic field, and a fourth magnet row, which are provided in the first magnetic circuit device and are arranged on both sides in the width direction of the first magnet row;
Provided in the second magnetic circuit device, on both sides in the width direction of the front Stories second magnet row, first for the horizontal magnetic field generating said being sandwiched therebetween facing the third magnet array and a fourth magnet array disposed gap space 5 magnet rows and 6th magnet row;
A first drive mechanism that relatively drives the third magnet row and the fourth magnet row along the row direction with respect to the first magnet row;
A second drive mechanism that relatively drives the fifth magnet row and the sixth magnet row along the row direction with respect to the second magnet row;
During the relative driving of each magnet row by the first drive mechanism and the second drive mechanism, between the first magnet row and the third magnet row and the fourth magnet row, and between the second magnet row and the fifth magnet row. Bei example of a magnetic circuit unit for canceling to mitigate or cancel the attractive and repulsive force generated between the magnet array and the sixth magnet array,
The canceling magnetic circuit device includes a canceling seventh magnet row and an eighth magnet row arranged further outside in the width direction of the third magnet row and the fourth magnet row,
A ninth magnet row and a tenth magnet row for cancellation arranged further outside in the width direction of the fifth magnet row and the sixth magnet row,
The seventh magnet having the same arrangement cycle of the magnets constituting the seventh magnet row and the eighth magnet row as the arrangement cycle of the magnets constituting the first magnet row and corresponding in the width direction. The magnetization directions of the magnets constituting the rows and the eighth magnet row and the magnets constituting the first magnet row are reversed or all the same,
The ninth magnet having the same arrangement cycle of the magnets constituting the ninth magnet row and the tenth magnet row as the arrangement cycle of the magnets constituting the second magnet row, and corresponding in the width direction. An insertion light source characterized in that the magnetization directions of the magnets constituting the row and the tenth magnet row and the magnets constituting the second magnet row are all reversed or the same . The first drive mechanism includes a pair of crank mechanisms having a common crankshaft, whereby the third magnet row and the fourth magnet row can be driven to reciprocate in opposite directions. The insertion light source according to claim 1 . The insertion light source according to claim 2 , wherein a weight portion having a flywheel effect is provided on the crankshaft. A base member that supports the third magnet row and a base member that supports the fourth magnet row are provided separately, and a linear guide mechanism that guides a horizontal plane and a vertical plane of each base member is provided. The insertion light source according to claim 3 . The second drive mechanism includes a pair of crank mechanisms having a common crankshaft, and is configured such that the fifth magnet row and the sixth magnet row can be driven to reciprocate in opposite directions.
The insertion light source according to claim 3 or 4, further comprising a synchronization mechanism that synchronously drives the first drive mechanism and the second drive mechanism. A first magnetic circuit device and a second magnetic circuit device arranged so as to sandwich a gap space through which an electron beam passes;
A first magnet array for generating a magnetic field provided in the first magnetic circuit device;
A second magnet row for generating a magnetic field, provided in the second magnetic circuit device, and disposed opposite to the first magnet row across the gap space;
A third magnetic array for magnetic field generation provided in the first magnetic circuit device and disposed on one side in the width direction of the first magnetic array;
A fourth magnet row for generating a magnetic field provided in the second magnetic circuit device and disposed opposite to the third magnet row with the gap space on one side in the width direction of the second magnet row;
A first drive mechanism that relatively drives the third magnet row in the row direction with respect to the first magnet row;
A second drive mechanism for relatively driving the second magnet row in the row direction with respect to the fourth magnet row;
A canceling magnetic circuit device that reduces or cancels the attractive repulsion force that occurs during the relative driving of each magnet array by the first driving mechanism and the second driving mechanism,
The canceling magnetic circuit device includes a fifth magnet row for cancellation arranged on the outer side in the width direction opposite to the side where the first magnet row of the third magnet row is arranged,
The Bei give a sixth magnet array for canceling disposed outside in the width direction of the side opposite to the second side of the fourth magnet array of the magnet array are arranged,
Magnets constituting the fifth magnet row that have the same arrangement cycle of the magnets constituting the fifth magnet row and the arrangement cycle of the magnets constituting the first magnet row and corresponding in the width direction. And the magnetization directions of the magnets constituting the first magnet row are all reversed or all the same,
A magnet constituting the sixth magnet row, wherein the arrangement cycle of the magnets constituting the six magnet row and the arrangement cycle of the magnets constituting the second magnet row are the same, and corresponding in the width direction; The insertion light source is characterized in that the magnetization directions of the magnets constituting the second magnet row are all reversed or all the same .

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